mouse hover tool tips for geom_point formatting

Question

This answers states that formatting tool tip (which is shown when mouse is hovered over scatter plot in plotly) can be done via text aesthetic of geom_point BUT in my another question I was told that text should not be used as aesthetic for geom_point (it is working but sometimes it causes problems please refer to my second link). So where is the truth? My goal is to create tool tips which I can format (set specific parameters as stated in first mentioned link) for geom_point.

Answer 1

Place the aesthetic mapping under ggplot instead of geom_point to avoid the warning:

## This produces an "unknown aesthetic" warning
ggplot( mtcars, aes( x = wt, y = mpg ) ) + geom_point( aes( text = cyl ) )

## This doesn't
ggplot( mtcars, aes( x = wt, y = mpg, text = cyl ) ) + geom_point()

Also, consider using key aesthetic in place of text when adding simple information. The former preserves the column label.

When doing aes( ..., text = cyl ), the mouse-over label will look like this:

# wt: 2.620
# mpg: 21.0
# 6

When doing aes( ..., key = cyl ), the mouse-over label will look like this:

# wt: 2.620
# mpg: 21.0
# cyl: 6